22 TROP. LEPID. RES., 23(1): 22-31, 2013 VAN DER POORTEN: Immatures of Pieridae in Sri Lanka NEW AND REVISED DESCRIPTIONS OF THE IMMATURE STAGES OF SOME BUTTERFLIES IN SRI LANKA AND THEIR LARVAL FOOD PLANTS (LEPIDOPTERA: PIERIDAE). PART 1: SUBFAMILIES PIERINI (IN PART) AND COLIADINAE George van der Poorten and Nancy van der Poorten 17 Monkton Avenue, Toronto, Ontario M8Z 4M9 Canada; Email: [email protected] Abstract - The immature stages of 11 of the 28 species of Pieridae in Sri Lanka and their larval food plants are presented, two of them for the first time. The nine other species are compared to prior descriptions and their larval food plants confirmed and new ones identified. This study provides some base information needed for conservation management programs for butterflies in Sri Lanka and for further studies on the biology of these species. Key words: Immature stages, larval food plants, Sri Lanka, Ceylon, Pieridae, Coliadinae, Pierini, Lepidoptera, butterflies, conservation INTRODUCTION necessary in conservation management planning. In the current study (conducted from 2004 to the present and A comparison of the latest published National Red List ongoing), we have documented the immature stages and larval data on the butterfly fauna of Sri Lanka to historical records food plants of 180 of the 245 known species of butterflies in Sri (e.g. Ormiston, 1924; Woodhouse, 1949) suggests that the Lanka. For more details on the background and approach, see populations of many of the 245 species known in the country van der Poorten & van der Poorten (2011). In Sri Lanka, there have declined. The National Red List 2012 of Sri Lanka lists 21 are 28 species of Pieridae in two subfamilies: Pierinae (Tribes species as CR (critically endangered), 29 as EN (endangered), Colotini (1 genus, 5 species) and Pierini (9 genera, 15 species)) 38 as EN (endangered), 40 as VU (vulnerable), 20 as NT (near and Coliadinae (2 genera, 8 species). In Part 1, we present the threatened) and 6 as DD (data deficient) (van der Poorten, immature stages and larval food plants of 11 of the 13 species 2012). Among the Pieridae, two are CR (Cepora nadina, Appias of the family Pieridae, subfamily Pierinae, tribe Pierini (genus indra), one is EN (Prioneris sita), five are VU (Colotis fausta, Appias, 5 species) and subfamily Coliadinae, (Catopsilia (3 Co. aurora, Co. danae, Eurema ormistoni, E. laeta) and one NT species) and Eurema (5 species)). The immature stages of two (Co. etrida). As with many other countries, the loss of habitats species and their larval food plants in Sri Lanka are documented along with larval food plants seems to be the main cause for for the first time; those of two species remains unknown. The these declines. immature stages of two species previously described from Sri To address these declines, the Biodiversity Secretariat of the Lankan material and of six species from Indian material are Ministry of Environment of Sri Lanka is developing a Butterfly compared to the findings of the current study and additional Conservation Action Plan. However, in order to assess the status observations are presented and larval food plants documented. of a butterfly species and to prepare conservation management For seven of these eight species, new larval food plants are plans, information on the biology of the species including the reported for the first time. For five of these eight species, larval larval food plants and the resource needs of the adults as well as food plants previously reported in Sri Lanka are confirmed. of the immature stages is a prerequisite. One species (Catopsilia scylla) was previously described in full However, the immature stages and larval food plants of the from Sri Lankan material (van der Poorten & van der Poorten, butterflies in Sri Lanka are incompletely known. Woodhouse 2012a). (1949) published information of the immature stages and larval food plants of 191 of the 242 species of butterflies in the island MATERIALS AND METHODS known at that time but the information for 111 of these species was based on work done in India, which does not necessarily Rearing methods: see van der Poorten & van der Poorten apply to the Sri Lankan populations. Little research has been (2011). Photography: see van der Poorten & van der Poorten published since then. (2012b). Nomenclature after K. Kunte (pers. comm.) and Knowledge of immature stages and larval food plants, as Yata (where referenced). Identification of plants: Plants were well as being important for conservation planning, is also useful identified to species if possible using several references (most in classification, elucidating broad-scale evolutionary patterns, notably, the series A revised handbook to the flora of Ceylon understanding ecology at the community and population levels, (Dassanayake (ed.)) and an inspection of herbarium specimens and in ecological chemistry (DeVries, 1986 and references at the Herbarium of the Royal Botanic Garden in Peradeniya, Sri therein). Little research has been published since then (except Lanka as well as consultation with botanical experts including see van der Poorten & van der Poorten, 2011, 2012). Dr. Siril Wijesundara and Jacob de Vlas. Where information The purpose of the current study is therefore to document on the duration of developmental stages is given, these data the immature stages and larval food plants of the butterflies in were obtained in rearings at ambient temperatures (22–34ºC) Sri Lanka to assist in the proper documentation of the status at Bandarakoswatte (07.37.01N, 80.10.57E), 70 m asl, North of a particular species and to provide the baseline information Western Province, Sri Lanka. Conventions used (applied to VAN DER POORTEN: Immatures of Pieridae in Sri Lanka TROP. LEPID. RES., 23(1): 22-31, 2013 23 both the larva and the pupa): Segments are numbered S1 to S14 in Sri Lanka but in India, the final instar larva and pupa have (S1—the head; S2 to S4—the 3 segments of the thorax; S5 to been described briefly by Davidson & Aitken (1890) and S14—the 10 segments of the abdomen). In the photographs, the Davidson et al. (1897) and in detail by Bell (1913b) (including head is always on the left. the egg (Fig. 1a)). The results of the current study agree with these descriptions except for the following: a) in the larva, the RESULTS AND DISCUSSION gonads are visible through the transparent skin and the flange is white to bluish-white and the tip of the anal process is a pale Family: Pieridae, Subfamily: Pierinae, Tribe: Pierini reddish (Fig. 1b); and b) in the pupa, the subdorsal row of spots are cream-colored, not yellow, and the ground color of the pupa Appias indra narendra Moore, 1877. Plain Puffin. ranges from light green to pale translucent greenish-brown; Endemic subspecies. most pupae have a few black spots randomly distributed about The immature stages and larval food plant of A. indra the body (Figs. 1c, d). narendra have not been described in Sri Lanka. Kunte (1998) Additional notes on immature stages: 1st instar: upon has described one of the subspecies found in India and has emergence, head pale yellowish-orange, body pale yellowish- recorded the larval food plants as Drypetes oblongifolia and green with minute setae, each with a sticky droplet at the apex; Putranjiva roxburghii (Euphorbiaceae/Putranjivaceae) (Kunte, from S2–S14 numerous light brown spots closely spaced to 2006). In the course of the current study, adults have been seen form a broad obscure lateral band; flange whitish; two stubby at only a few locations and no eggs, larvae or pupae have been anal processes; larva appears oily and translucent; day two: found. similar but head greenish-yellow; body yellowish-green (Fig. 1e). 2nd: not recorded. 3rd: head yellowish-orange with minute Appias libythea libythea (Fabricius, 1775). Striped setae; body cylindrical, each segment transversely impressed Albatross. with 5–6 parallel lines, each partition with 6–8 setae, each with The immature stages of A. l. libythea have not been described a sticky droplet at the apex, obscure darker green spots between the impressed lines; ground color yellowish-green, a darker green from S3–S8; dorsal line pale green and indistinct (Fig. 1f). 4th: similar to 3rd except head pale green, body bluish-green, spiracular line faint, obscure, whitish; flange light grayish-blue to white; each transversely impressed region carries a series of purplish spots (Fig. 1g). In the 5th instar, the sticky droplets are not evident and the larva is covered with a dense coating of setae. The larva looks similar to that of A. libythea olferna from Singapore (Butterfly Circle, 2012a). Duration of immature stages (days): pupa (4–5). Larval food plants: In Sri Lanka, de Nicéville & Manders (1899) reported “the larva as usual in the genus feeds on Capparis but it also eats the leaves of Crataeva” [sic]. The current study showed for the first time that Crateva adansonii, Cadaba fruticosa, Capparis roxburghii and Capparis grandis (Capparaceae) are used as larval food plants. Though Woodhouse (1949) quoted Capparis sepiaria and Cap. horrida from Indian sources (Bell, 1913b), we have never observed larvae on these plants. The first two instars require tender leaves but later instars feed on more mature leaves. A. l. libythea is common and widespread in the dry, intermediate and arid zones. It has also been recorded in the wet zone and the higher hills but is a migrant in these areas and not resident. Crateva adansonii is widespread in the arid, dry and dry-intermediate zones and seems to be the preferred larval food plant in these areas. Cadaba fruticosa is restricted to the arid and dry zones of the west coast. Capparis roxburghii is widespread in the arid, dry and dry-intermediate zones and seems to be used only when tender leaves of Crateva adansonii are not available.